Your browser is out-of-date!

Update your browser to view this website correctly. Update my browser now


Innovations: Grass Valley AMPP Audio Mixer

A number of hardware solutions for remotely mixing audio have emerged over recent times, but Grass Valley has gone a step further, unveiling its cloud-based AMPP Audio Mixer.

Grass Valley AMPP Audio Mixer
Grass Valley AMPP Audio Mixer

There’s little doubt that the pandemic has fueled technical innovation, focusing minds on new solutions to the challenges presented by working from home. A number of hardware solutions for remotely mixing audio have emerged over recent times, but Grass Valley has gone a step further, unveiling its cloud-based AMPP Audio Mixer.

The new product is the latest extension of Grass Valley’s AMPP or Agile Media Processing Platform, a SaaS solution for remote and distributed productions. The platform is the result of a project to bring cloud technologies to television broadcast, says Mike Cronk, Grass Valley’s VP of advanced technology and chairman of the board for AIMS, the open-standards IP advocacy group.

There are a lot of technical challenges, he says, such as handling latency, aligning signals and managing time and bandwidth. “We worked on solving those technical problems, got about 17 patents and built a platform that is able to do live production in the cloud. And, if you can solve live production in the cloud, you can also do playout and other post production functions, which are also moving that way.”

The AMPP platform is part of the Grass Valley Media Universe, says Cronk. “We want to build an ecosystem of partners, not just Grass Valley, to provide other software applications and services to bring the capabilities of elastic compute to the industry in a meaningful way, so they can use that to improve their businesses.”

Blizzard Entertainment was the first to put the AMPP Audio Mixer to work, using it on eSports broadcasts in early 2020, he reports. The user base has since grown to include broadcast networks, corporate events and even certain aspects of the Super Bowl.

“Because human ears are so keen on differences and latency between different audio signals, that’s driven the industry to do a lot with dedicated hardware. It takes time to put that into software,” he notes. Since Grass Valley solved some of those issues in a software world with the AMPP ecosystem, he says, “We were able to exploit that and build the Audio Mixer.”

The mixer is an app that runs on a computer and may be controlled via a touch screen or mouse. “That computer could be in AWS, Microsoft Azure or Google Cloud. It also could be running on a general-purpose server right next to you. You run that application up and it serves an HTTPS HTML5 interface.” Multiple instances will run simultaneously on the platform.

The mixer currently offers a feature set that supports productions up to a certain size: 64 audio stems or inputs, eight subgroups, 16 output mixes—enabling the creation of mix-minus feeds or aux sends—plus a main out and eight VCA groups. There’s comprehensive EQ, filters and compression assignable to all inputs, outputs and groups.

For those preferring tactile control, says Cronk, “A lot of our first customers have been using the Behringer X-Touch Compact,” which offers nine faders, 16 rotary encoders and 39 buttons. “We have a service that can run locally that allows you to map any key on a MIDI panel to any function.”

Audio is introduced into the AMPP platform via SMPTE ST 2110-30/AES67, SDI and NDI. “The other thing we do, especially over the WAN and in-cloud, is encode in Opus, which is pretty efficient and low latency,” he says. “Once the audio lands on a compute node that’s under AMPP control, if it’s compressed, we decompress it and we deal with PCM audio.”

The mixer UI incorporates a video program monitor panel, and because the platform carries uncompressed video and metadata, assigning an audio input with associated video brings up a keyframe thumbnail on that channel. An AV multiplexer on each mixer output channel can marry audio to its associated video, with delay compensation, without the need for external apps, he says.

While the AMPP Audio Mixer won’t be handling any super-complex productions quite yet, this is just the initial version and it’s being well received, Cronk reports: “People have found it very intuitive and have been able to up the level of their productions. This is a tool that is groundbreaking in terms of its capabilities in the cloud. We’re really excited about it.”